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Hello, our new 'used' baby grand will be arriving next week Saturday and we are so looking forward to having it placed in our living room for our kids to start playing beautiful music on it.

Total house size (basement, main floor and 2nd floor) is about 2200 sq ft. We are in Ottawa, Canada; cold, dry winter (gas furnace to heat) and can be humid and hot summer (central A/C to cool). Piano will sit in the living room. We have a smal capacity dehumidifier right now for the basement which we turn on for the summer season only. I know we need to maintain 40%-50% humidity level for the piano. Do we need to get another dehumidifier for the main floor? I am not sure if the unit in the basement is sufficient to maintain humidity level for the entire house. Any advise to help me maintain the right temperature to keep the piano in top shape is greatly appreciated.

I'm in the same boat and my 1 year old grand has to suffer through roughly 20% humidity in the winter to horribly humid in the summer.I've got two cheap humidity meters and today one of them says 70% and the other says 80%! I've decided to buy a Dampp-Chaser system for the piano. People swear by them and it is much more convenient (and effective) than trying to keep the room a constant humidity. The humidity swings are just too extreme here, and I believe Ottawa is fairly similar. You should buy yourself several of those cheap humidity meters, I got mine online. They are only a few bucks, and even though they probably aren't' terribly accurate they certainly give you a ballpark value.

We have similar climate in WI, and I'm with Sparky - get a Dampp-Chaser (unless you want to spend a large chunk of money to install a whole house humidity control system). Temperature is easy to maintain, but in a climate like yours, humidity is not. The dehumidifier in the basement will never maintain humidity in the whole house. And you probably don't want a dehumidifier on the main floor for 2 reasons: 1) noise; 2) the unit creates heat. Do you really want to try to vent that heat to the outside? I didn't think so.

The A/C may adequately control humidity in the middle of summer when it is frequently running, it's another story during spring and fall or if you like to open windows. For example, right now it is 64 F and 94% humidity in Ottawa. As that humidity seeps into your house, do you really want to be running the A/C? Also, when temps get below 60 F, some A/C condensers can freeze and become damaged.

In the winter, keeping humidity up (above 35%) will be the challenge, even with a whole house humidifier. Plus, as outdoor temp drops so does the recommended indoor humidity. For example, the recommended indoor humidity is no more than 25% when outside temp is 0 F (-18 C). If you try to get indoor humidity to 40%, you run risk of mold or structural damage to your house.

PaintedPostDave
500 Post Club Member
Registered: 06/09/10
Posts: 663
Loc: Upstate New York

If you already have A/C then that means you have forced air, as do I. When I got my grand I had a humidifier installed on the furnace. Our winters in upstate NY are dry also and this last winter was a relative pleasure in that there was no itchy skin, static shock from carpet and upholstery, no more cracked fingertips, etc. The winter humidity stayed around 35%-40% and I am sure my Knabe appreciated it. Get a whole house humidifier.

I live north of Pittsburgh and have a new high-efficiency furnace that includes a humidifier that is installed in the main duct coming out of the top of the unit. All last winter my humidity in the house ranged between 35%-40% like PaintedPostDave. Also I have central air, and the humidity stays within that range later in the summer when I run the AC. My house is similar in size to yours. My grand piano is very happy!

Again, when AC runs you may be able to control the humidity somewhat, but this time of year may be a different story. If you have an older house or like to open windows/doors you have no good way to control humidity. For example, the humidity in my 60 yr. old house has been around 60% for the last couple of days. Running the AC isn't an option because it is 70F inside.

A separate question you may ask yourself is how important is it to keep humidity w/in that 40-50% humidity level?

If you purchase a humidistat be sure to calibrate it since they can be very inaccurate. Google calibrate humidistat to find out how.

Thanks for those links BHB.The chart in the second link explains why I can never raise my humidity in my place over about 20% in the winter. (I have a full house humidifier attached to the furnace). When it is cold out too much condensation forms on the windows and then ice. And in the summer because I enjoy it so much I like to leave the doors and windows open as much as possible. I don't want to be boxed in the with A/C going all the time and it doesn't get too hot here anyways, just very humid.

Your welcome. With the recommended humidity for pianos often being discussed in these forums, I feel it important to let those in northern climates understand that that can create other problems. I learned much of this when I purchased my piano last December and talked to a HVAC specialist about humidity control. The mildew & mold risks have made me very cautious about too high indoor humidity in winter.

I too like windows open whenever possible and obviously that means higher humidity at times. While a Dampp-Chase keeps the humidity level for the soundboard more stable, it would be interesting to know if any study has been done to determine the real long term effects of not regulating humidity and if the pianos that have been around much longer than climate control are outliers or the norm.

Your welcome. With the recommended humidity for pianos often being discussed in these forums, I feel it important to let those in northern climates understand that that can create other problems. I learned much of this when I purchased my piano last December and talked to a HVAC specialist about humidity control. The mildew & mold risks have made me very cautious about too high indoor humidity in winter.

I too like windows open whenever possible and obviously that means higher humidity at times. While a Dampp-Chase keeps the humidity level for the soundboard more stable, it would be interesting to know if any study has been done to determine the real long term effects of not regulating humidity and if the pianos that have been around much longer than climate control are outliers or the norm.

Take a look at my Facebook page for a gallery of damage caused by too-low humidity. Dampp-Chaser has been in business for 60 years. Humidity effects on pianos and pretty much anything made of wood are well-known.

Thanks Cy. I don't doubt the insurance that a Dampp-Chaser system can provide and know that there is literature on optimal temp/humidity for preserving wood based products.

I was just curious about all of those 80 - 100 yr old pianos that never had a Dampp-Chaser and were in houses with no humidity control for the 1st 1/2 of their lives. What commonality exists for those that survive today vs. those that have cracked soundboards, bridges separating from soundboards, etc. Were they the best of the breed or something else?